AP3D1 (AP-3 complex subunit delta-1) encodes the delta 1 subunit of an adaptor protein regulating intracellular vesicle-mediated transport (19631730). Lack of expression of functional AP-3, leads to a deficiency in vesicle transport and storage, which affects neurotransmitter vesicle turnover and release in the central nervous system (19032734). The AP-3 complex facilitates the budding of vesicles from the golgi membrane, and directly involved in trafficking to lysosomes. It is implicated in intracellular biogenesis and trafficking of pigment granules and possibly platelet dense granules and neurotransmitter vesicles.